Positioning device



Feb. l0, 19742. 1 'E'. BARTH 2,272,929

yPOS TIONING DEVICE Filed July 25, 1939 Patented Feb. 10, 1942 2,272,929 PosITIoNING DEVICE Jay E.

assignments, to

Barth, Detroit, Mich., assigner, by mesne Philco Radio and Television Corporation, Philadelphia, Pa., a corporation oi' Delaware Application July 25, 1939, Serial No. 286,490

(Cl. 'i4-125) 6 Claims.

This invention relates to positioning devices and, more particularly, to means for actuating two step-by-step devices in correlation with one another, employing a single manual actuator for eifecting such actuation,

while the invention is broadly applicable te actuator, and there is also disclosed the specific application of such means to the tuning of a radio receiver by means of a single push-button. The present invention is directed to a specific mechanism of this character, the details of which are also shown in the said Quinn application.

A particular difilculty found to be prevalent with many constructions of switches suitable for use according to the teaching of the said Quinn application is the tendency for the tuning device or the tuning indicator to operate independently of the other device. Such actuation might result, for example, from carelessness on the part of the operator. As an illustration, one form of device which might be used for the purpose of tuning a radio receiver according to the principles of the aforementioned Quinn application may comprise a single manually operable plunger positioned in proximity to the movable members of the tuning unit and the indicating unit, the plunger carrying operating pawls or other members directly on itself for actuating ratchets associated with the said units. Such an assembly is often subject to maladjustment which permits either the tuning unit or the indicating unit to function independently. By the present invention, there is provided a novel device employing a tandem linkage which prohibits such faulty operation.

The principal object of the invention, therefore, is to provide a novel mechanical structure for actuating two devices in step-by-step f correlation with one another, employing a single manual actuator.

A more specific object of the invention is to provide a novel mechanism which is particularly adapted for operating a tuning device and a tuning indicator in a radio receiver, utilizing a single manual control for this purpose.

Sti11 another object of the invention is to provide a mechanism having two devices to be positioned. a primary actuating element for positioning one of said devices on its return motion, and a linkage for causing tandem operation of said two devices.

Other objects and features of the invention will appear hereinafter.

In the drawing:

Fig. 1 is a side elevational view of the mechanism provided by the invention;

Fig. 2 is a face view of the mechanism looking at the same from the underside of Fig. l;

Fig. 3 is a similar view, with certain elements omitted for the sake of clarity, illustratingr the parts at a certain stage of operation; Y

Fig. 4 is a similar view illustrating the parts at a later stage of operation; and

Figs. 5 to 8 are perspective views of certain parts of the mechanism.

Referring to the drawing, and particularly the principal figures thereof, the two devices whose positions are to be controlled are designated generally by reference characters l0 and Il. The device Iii is a multi-section rotary switch adapted to control pretuned circuits of a radio receiver, so that the receiver may be tuned to any one of a plurality of predetermined stations by actuating the switch in step-by-step fashion. Such devices are now well known and require no detailed description. The device Il .is a tuning indicator having provision for carrying suitable indicia representing respectively the stations to which the radio receiver may be tuned by the rotary switch IU. By means of the mechanism provided by the invention. the two said devices are operated step-by-step in correlation with one another by means of a single manual actuator.

It will be understood that the two devices I0 and ll are representative of any two devices whose position it is desired to control. and the lnvention is not restricted to the specic devices illustrated or the specific application to the tuning of a radio receiver.

Referring now to Fig. l. the tuning device l0 comprises a plurality of switch sections, in the present instance two such sections i2 and I3 being employed. Each of these sections comprises a switch structure of the wafer type and includes a stationary insulating plate or ring I4 carrying stationary circularly arranged contacts l5, the inner portions oi which are engageable by a rotating Contact (not visible) carried by a common rotatable shaft I6. The stator plates are carried by Supports I I which are mounted on the base plate I8, and the rotatable shaft I6 is suitably journaled in the base plate and extends therethrough. Since switches of the character here illustrated are well known, it is believed that the present illustration will suice for the purpose of explaining the present invention, particularly since the invention is not concerned with the specic details of the switch structure.

Below the base plate I8, as viewed in Fig. 1, the shaft I6 carries a ratchet I9 (see Figs. 2 to 4), on the opposite sides of which are spaced disks 29 which serve to guide and support an end of a reciprocable bar 2 I, the purpose of which will be explained presently.

The tuning indicator II comprises a shaft 22 which is rotatably carried by base plate I B 1n spaced relation to the tuning device. A star wheel 23 is mounted on shaft 22, and on the face or side of the star wheel nearest the base plate I8, there are circularly arranged turned out lugs 24 (see Fig. 8) which serve as a ratchet mechanism in the manner hereinafter described. An indicator drum 25, having suitable provision for carrying indicia thereon, is mounted upon shaft 22 so as to rotate therewith. One suitableindicia holder forms the subject of a copending application of Jackson H. Pressley, Serial No. 286,486, filed July 25, 1939.

As shown in Figs. 2 to 4, an actuating member 26 is slidably mounted on the base plate I8, and

to this end the said member 26 is provided with.

slots 21 and 28accommodating pins 29 and 30 projecting from the base plate. The end 3I.of member 26 is adapted to receive a suitable pushbutton element (not shown), so `that the said member may be moved toward the left, as viewed in Fig. 2, by depressing the said push button. A spring 32 has one end secured to member 26 at 33 and` has its other end secured to the base plate I8 at 34. This spring serves to maintain the member 26 in the extreme right hand position shown in Fig. 2, and also serves to move the said member to this normal position when the push-button is released following each operation by an operator. A resilient finger 35 (see Fig. 7) is riveted to member 26 at 36 and has a turned end 31 seated in a recess 38 of member 26 so as to prevent rotary movement of the said nger. The opposite turned end 39 of the resilient iinger is operatively associated with the turned-out lugs 24 on the star wheel 23, and constitutes an operating pawl for .the ratchet means comprising the said lugs. In the normal position of the parts shown in'Fig. 2, the end 39 of the resilient finger is disposed between two of the lugs 24, and when the member 26 is moved toward the left to the position illustrated in Fig. 3, the end 39 rides over one of the lugs 24 and is then in a position to push'against the said lug and thus advance the star wheel 23 one step when the member 26 is released. In Fig. 4, the parts are shown at the instant that the member 26 is near the end of its return stroke, and it will be noted that the end of finger 35 is in operative engagement with one of the lugs 24.

To assist in clarifyingT the drawing, in Figs. 3 and 4 the indicator drum 25 and the outer guide disk 20 have been removed.

Referring now to the bar 2I, of which mention has been previously made, this element is provided near one end with a 'slot 4U which accommodates a pin 4I projecting from the base plate I8. The opposite end of the bar is formed as illustrated and projects within the space between the disks 29. Thus, the bar is reciprocably mounted upon the base plate, and it is normally maintained in its extreme right hand position by a spring 42 having one end secured to bar 2| at 43 and having its other end secured to the base plate I8 at 44. the bar 2I, shown more clearly in Fig. 5, is of step-like formation, thus providing the extension 45 in operative association with the teeth of the star wheel 23. Normally, the extension 45 is disposed between two of the said teeth, as shown clearly in Fig. 3. It will be noted that each tooth of the star wheel has a curved edge 46 which serves as a cam to operate the bar 2| through the medium of the extension 45 thereof. `When the star wheel is advanced, as mentioned above and as depicted in Figs. 3 and 4, the star wheel tooth to the right of extension 45, as viewed in these gures, cams the bar 2I toward the left until the point of the tooth passes beyond the extension 45, at which time the spring 42 is effective to return the bar 2|, causing the extension 45 to enter the space between the said tooth land the next adjacent tooth of the star wheel.

At the opposite end of the bar 2I, there is provided a pawl 41 which operates to step the ratchet I9 each time the bar 2I is actuated in the manner above described. There is also provided at the same end of bar 2| a relatively short projection 48 having a nat end adapted to cooperate with a at edge of each ratchet tooth as illustrated in Fig. 4. As may be seen in Fig. 3, when the bar 2I is moved toward the left from its normal position, the pawl 41 engages the ratchet I9.V advancing the same, and shortly after, the extension 48 engages one of the ratchet teeth thus limiting the advancement of the ratchet to one step. In this manner, the ratchet I9 is advanced one step for each actuation of the bar 2 I It will be observed that on the return movement of bar 2I from the position shown in Fig. 4 to the position shown in Fig. 2 the pawl 41 is cammed downward by a tooth on ratchet Wheel I9. To permit this angular motion of bar 2I, which is desirable to accommodate a long stroke for bar 2I with a relatively small diameter ratchet I9, only one support or guide pin 4I is used, the guide discs 20 and the spring 42 positioned at an appreciable angle to the longitudinal axis of bar 2I, serving to support the pawlV end of the bar.

It may now be noted that a pin 5I on member 26 prevents movement of the star wheel 23 when member 25 is in normal position, as shown in Fig. 2. Additionally, there is preferably provided a spring finger 49 (see Fig. 6) attached to base plate I8 and having a free end 50 resiliently engaging the star wheel to impose a frictional drag thereon, thus preventing slight movements of the star wheel which would otherwise be premitted by lost motion of the parts. This is of particular advantage in the case of an automobile receiver since the vibrations would tend to oscillate the indicator 25.

It will be noted that the two ratchets on the shafts I6 and 22 have the same number of teeth, and the star wheel 23 likewise has the same number of teeth, so that the two shafts have corresponding positions to which they are advanced by the mechanism illustrated. Thus, the two devices I0 and II are operated step-by-step in correlation with one another. As applied to The right hand end of the tuning of a radio receiver, the mechanism advances the tuning device l one step each time the push-button mounted on the end 3|v of the member 26, is depressed and, at the same time, it advances the tuning indicator Il one step. In this manner, the radio receiver is tuned to successive stations and the tuning indicator is positioned accordingly.

While the invention has been described with particular reference to the control of a radio receiver, as previously stated, the invention is.

broadly applicable to the step-by-step positioning of two devices in correlation with one another. Moreover, it will be apparent that the invention is capable of modification within the scope of the appended claims.

l. A positioning device comprising a first rotatable shaft to be positioned; ratchet means on said shaft having a predetermined number of ratchet teeth; a manually-operable pawl for operating said ratchet mean to thereby rotate said shaft step-by-step; a second rotatable shaft to be positioned. said second shaft being spaced from said first shaft; ratchet means on said second shaft having the same number of ratchet teeth as said rst ratchet means; a second pawl longitudinally movable and extending between said first and second shafts for operating the ratchet means on said second shaft; and a star ff:

wheel having the same number of teeth as the two aforesaid ratchet means and operable'by the ratchet means on said first shaft for moving said second pawl longitudinally, the teeth of the two ratchet means and the star wheel being reltf atively orientated so as to rotate said second shaft in step-by-step correlation with said first shaft.

2. A step-by-step positioning device, comprising a frame member, a member to be rotated, a ratchet wheel on said rotatable member, an elongated driving pawl for'said ratchet wheel, resilient spring means supporting one end of said pawl from said frame member in cooperative relation with said ratchet wheel, means supporting the other end of said pawl on said frame member for longitudinal and pivotal movement of the pawl, and means for effecting recurring longitudinal movement of said pawl to step said ratchet wheel.

3. A step-by-step positioning device, comprising a frame member, a member to be rotated, a ratchet wheel on said rotatable member, an elongated driving pawl for said ratchet wheel, resilient spring means supporting one end of said pawl from said frame member in cooperative relation with said ratchet wheel, said spring means being arranged to hold the pawl normally out of driving engagement with the ratchet wheel, guide means for the said end of the pawl, means supporting the other end of said pawl on said frame member for longitudinal and pivotal movement of the pawl, and means for effecting recurring longitudinal movement of said pawl to step said ratchet wheel.

4. A step-by-step positioning device, comprising a frame member, a member to be rotated, a ratchet wheel on said rotatable member, an elongated driving pawl for said ratchet wheel, resilient spring means supporting one end of said pawl from said frame member in cooperative relation with said ratchet wheel; said spring means being arranged to hold the pawl normally out of driving engagement with the ratchet wheel, guide means for the said end of the pawl, means supporting the other end of said pawl on said frame member for longitudinal and pivotal movement of the pawl, a rotatable driving member spaced from said first rotatable member, and means on said driving member for effecting recurring longitudinal movement of said pawl to step said ratchet Wheel.

5. A step-by-step'positioning device, comprising a frame member, a member to be rotated, a ratchet wheel on said rotatable member, an elongated driving pawl for said ratchet wheel, resilient spring means supporting one end of said pawl from said frame member in cooperative relation with said ratchet wheel, said spring means being arranged to hold the pawl normally out of driving engagement with the ratchet wheel, guide means for the said end of the pawl, means supporting the other end of said pawl on said frame member for longitudinal and pivotal movement'of the pawl, a rotatable driving member spaced from said first rotatable member, and a star wheel on said driving member engaging said other end of said pawl for effecting recurring longitudinal movement of said pawl tostep said ratchet wheel.

6. A positioning device, comprising a first rotatable shaft to be positioned, manually operable means to rotate said shaft step-by-step through a predetermined number of positions during one revolution, a second rotatable shaft to be positioned, said second shaft being spaced from said first shaft, ratchet means on said second shaft adapted to advance said second shaft through the same number of positions as said first shaft, a longitudinally movable pawl extending between said first and second shafts for operating the ratchet means on said second shaft, and cam means on said first shaft having a number of cam projections corresponding to the number of said positions for moving said pawl longitudinally, said cam projections and said positions being relatively-orientated so as to rotate the second shaft in step-by-step correlation with said first shaft.

JAY E. BARTH. 

